1. Field of the Invention
The present invention relates generally to radiography and related calibration apparatuses and, more particularly, to a calibration apparatus that allows for efficient securing in an area of interest for positioning a calibration unit near a radiography target.
2. Description of Related Art
Many procedures in the medical field and otherwise use radiography to produce images for assessing radiopaque materials. One example is the use of radiography in taking orthopedic x-rays. An x-ray image must be calibrated in order to appropriately scale the joint and bone structure of the patient. Currently, for example, a 25.4 millimeter (approximately 1 inch) metal sphere is employed and placed near the area of interest in order for it to show up in the x-ray, for use in calibrating the image to scale using the known dimensions of the metal sphere.
Problems often arise when attempting to keep the metal ball in place during the x-ray process. Patients often lie on a horizontal or vertical table throughout the duration of the x-ray so options are limited for placement of the metallic ball without additional securing assistance.
According to the prior art, one solution currently on the market is an adhesive strip that is applied directly to the skin of the patient, regardless of the location, and the calibration sphere is then stuck to the back side of the strip. One problem with an adhesive strip is that it is generally uncomfortable for both the patient and the technologist to physically place the strip onto the body of the patient. This is particularly problematic where the skin of the patient has sores or is prone to tearing of the patient's skin upon removal. Another issue that commonly arises is that the body hair of the patient can be too intense for the strip to properly adhere given the weight of the calibration sphere.
Further, where the calibration sphere is taped near a radiographic target in a vertical position such as, for example, a patient's knee, while standing upright the strip may not be able to support the weight of the calibration sphere. In addition, the strip is uncomfortable and sometimes painful, or possibly damaging to the skin when removed upon completion of the x-ray. Many times the strip must be placed in a private area of the patient. Still further, the strips are disposable, creating a recurring expense for the owner and higher prices are then passed along to the patient or radiography facility.